Geometry Workshop Obergurgl 2021

Previous research on animations of soap bubbles, films, and foams largely focuses on the motion and geometric shape of the bubble surface. These works neglect the evolution of the bubble's thickness, which is normally responsible for visual phenomena like surface vortices, Newton's interference patterns, capillary waves, and deformation-dependent rupturing of films in a foam. In this talk, I will describe a model that incorporates these natural phenomena by introducing film thickness as a reduced degree of freedom in the Navier-Stokes equations. Using a suitable discretization, I will describe how the model can be turned into an incompressible fluid solver for 2.5D films, and present some of our simulations, which enhance state-of-the-art bubble solvers with additional effects caused by convection, rippling, draining, and evaporation of thin film. The equations of motion are simulated on a non-manifold triangle mesh surface. This presents an additional challenge in terms of maintaining an intersection- and inversion- free mesh throughout the simulation via the use of a surface tracker. In the second part of my talk, I will describe in detail the algorithmic challenges associated with surface tracking and how developments in the area can lead to better bubble simulations in the future.

Sadashige Ishida, Chris Wojtan, Fumiya Narita, Toshiya Hachisuka, and Huidong Yang.